Gripper point for loom projectiles with an external feed

ABSTRACT

The invention relates to a gripper point for loom projectiles with an external feed, which consists of a plate, a rocker strip pivoting on the plate, and a spring blade bearing resiliently on the rocker strip near its end, in order to press it against the plate, the plate and the rocker strip having in the area in which they are pressed against one another surfaces for gripping a weft thread, the plate being provided in addition with a hook for guiding the weft thread toward the gripping surfaces.

United States Patent Palencher 1 Dec. 16, 1975 GRIPPER POINT FOR LOOMPROJECTILES WITH AN EXTERNAL FEED 3,638,686 2/1972 Sole et a1. 139/122Primary Examiner-Henry S. Jaudon Attorney, Agent, or Firm-Seidel, Gonda& Goldhammer [5 7 ABSTRACT The invention relates to a gripper point forloorn projectiles with an external feed, which consists of a plate, arocker strip pivoting on the plate, and a spring blade bearingresiliently on the rocker strip near its end, in order to press itagainst the plate, the plate and the rocker strip having in the area inwhich they are pressed against one another surfaces for gripping a weftthread, the plate being provided in addition with a hook for guiding theweft thread toward the gripping surfaces.

8 Claims, 11 Drawing Figures U.S.' Pateht. -De c. 1 6, 1975 Sheet3 0f 43,926,225

Fig.8

US. Patent Dec. 16, 1975 Sheet 4 of4 3,926,225

MN a 8 N s 9 hw wA \IR a NN z c GRIPPER POINT FOR LOOM PROJECTILES WITHAN EXTERNAL FEED The invention relates to a gripper point for loomprojectiles with an external feed. The gripper point is characterized inthat it consists of a plate,'a rocker strip pivoting on the plate, and aspring blade bearing resiliently on the rocker strip, near its end, inorder to press it against the plate, the plate and the rocker striphaving in the area in which they are pressed against one anothersurfaces for gripping a weft thread, the plate being provided inaddition with a hook for guiding the weft thread toward the grippingsurfaces.

According to another characteristic feature of the invention, the plateand the pivoting rocker strip are positioned with respect to one anotherby a rib and a groove, one being on the plate, the other on the rockerstrip, this groove and rib determining the pivoting axis, that is tosay, a hinge.

The invention is illustrated by way of non-limitative examples in theaccompanying drawings in which:

FIG. I is an elevational view of one half of a loom projectile having agripper point according to the invention;

FIG. 2 is a plan view of FIG. 1;

FIG. 3 is a cross-section along AA of FIG. 1;

FIG. 4 is an elevational view of the plate of the gripper point;

FIG. 5 is a partially broken away view from below of FIG. 4;

FIG. 6 is a side view of the rocker strip of the gripper point;

FIG. 7 is a plan view of FIG. 6;

FIG. 8 is a view from below of FIG. 6;

FIG. 9 is an elevational view of the blade of the spring of the gripperpoint;

FIG. 10 is a cross-section along BB of FIG. 9;

FIG. 11 shows a cross-section similar to FIG. 3 of another embodiment ofthe gripper point mounted on a projectile.

The gripper points according to the invention are designed to be fittedonto each of the ends of a loom projectile with external feed, that isto say, a loom in which the weft threads come from spools locatedlaterally to the loom, the threads from these spools being altemativelygripped by the gripper points of the projecticle which make them passthrough the shed.

According to the invention, this gripper point consists of a plate 1, arocker strip 2, and a spring blade 3. The three components of thegripper point are fastened to the projectile 4, by means of screws 5engaged with the nuts 6 embedded in the projectile (see FIG. 3), anyuntightening of these screws being prevented by the presence of theretaining means 7 made of plastic material, protruding slightly from theinner wall of the nuts The screws 5 tighten the plate 1 and the springblade 3, between the heel 8 and the backing 9 of the projectile.

The rocker strip 2 comprises, on one of its faces, a rib 10 which lodgesinto a groove 11 of the plate 1, this rib 10 providing a pivotingarrangement of the rocker strip 2 on the plate 1.

Likewise, the pointed ends of the plate 1 and the rocker strip 2comprise support surfaces 12 and 12' respectively, which are locatedopposite one another and constitute the areas that grip the thread.

Likewise, these gripping surfaces, for a given thread, may or may not beprovided with additional deformations 13 and 13, made in the form ofribs 13 and grooves 13', the ribs 13 of the rocker strip 2 being of alength such that they slightly overlap the support or gripping surface12 of the plate 1.

The rocker strip 2 also comprises a tail 14 which extends beyond thepivot rib 10, the tail 14 being inclined in a manner such that its endfits through the elongated, central opening 18 provided in the springblade 3 (see FIGS. 1, 3, 9 and 10).

The spring blade 3 bears against the front end of the rocker strip 2, inorder constantly to tend to maintain the surface 12 of the rocker strip2 against the surface 12 of plate 1.

In addition, the rocker strip 2 comprises a tip 15, the contour of whichis made in a manner such that it continues the outer surface of the end16 of the spring blade 3 (see FIGS. 2, 3 and 11). The plate 1, providedwith a groove 11, comprises at its end a hook 17 which progressivelycurves from the plane of the plate 1 in a direction opposite the pointof the gripper point, this hook 17 being designed to guide a weft threadto be gripped toward the gripping surfaces 12 and 12' which may or maynot be provided with ribs 13 on the rocker strip 2 and complementarygrooves 13 on the plate 1.

The plate 1 also comprises, near its end, a border 19 which is prolongedby a plane part 20 that is set back, and on which the backing 9 isapplied, this arrangement preventing threads from being caught betweenthe backing 9 and the plate 1 when the projectile moves.

The gripper point, the end of which is machined into the shape of anogive, will then be able to grip with certainty a weft thread that is tobe passed through the shed, whatever the threads nature or thickness.The gripper point is opened simply by pressing a control componentagainst the end of the tail 14 which fits through the opening 18 of theblade of the spring 3. As may be readily seen from FIGS. 3 and 11,pressure on tail 14 will cause rocker strip 2 to pivot on rib 10 so thatsupport or gripping surface 12' will separate from gripping surface 12to open the gripper point and release a thread.

The gripper point, according to the invention, can also be provided witha means for regulating the tension of the spring and thus also thethread gripping force between the surface 12 of plate 1 and the surface12' of rocker strip 2. To this end (see FIG. 11) a screw 21 is fixed byits head 22 in the plate 1. This screw 21 passes through an orifice inthe spring blade 3 and engages on the opposite side of the blade 3, witha nut 23 lodged in the projectile 4. Nut 23 is provided with a split end24.

A portion of the screw 23 is lodged inside the nut 23 so as to lock thescrew 21 in the nut 23.

Thus, in this construction, by screwing the nut 23 down to a lesser orgreater degree with the aid of a screw-driver introduced into the splitend 24, the nut 23, by bearing on the blade 3, modifies the tension andthus the gripping force of the rocker strip 2 against the plate 1.

It is obvious that the invention is not limited to the examples of theembodiments hereinabove described and illustrated, and that on the basisof these, other forms and methods of embodiment can be envisaged withoutdeparting from the scope 'of the invention.

Whatl claim is: i

l. A gripper point for loom projectiles with an external feed,comprising a plate, a rocker. strip and a spring blade, said rockerstrip pivoting about an axis parallel to said plate and supported bysaid plate, said spring blade bearing resiliently on said rocker stripnear one end thereof in order to press said rocker strip against saidplate, said plate and said rocker strip having in the area in which theyare pressed against one another surfaces for gripping a weft thread, andsaid plate being providedwith a hook for guiding a weft thread towardthe gripping surfaces.

2. A gripper point according to claim 1 wherein the plate and the rockerstrip are positioned with respect to one another by a rib and a groove,one being on the plate, and the other on the rocker strip, the grooveand rib determining the pivoting axis. 7

3. A gripper point according to claim 1 wherein the surfaces that grip aweft thread have complementary deformations.

4. A gripper point according to claim 3 wherein the complementarydeformations on the gripping surfaces 4 extend beyond the grippingsurfaces toward the hook for guiding the weftthread.

5. A gripper point according to claim 1 wherein the rocker strip has atail extending beyond the pivoting support, while the spring blade hasan opening for the passage of the tail, the arrangement" of the tailbeing such that its end extendsthrough, the opening.

6. A gripper point according to claim ,1 wherein the rocker strip has atits end a tip, the contour of said tip continuing the profile of theouter surface of the spring blade. 1

7. A gripper point according to claim 1 wherein the plate has a borderat its end onthe face opposite the gripping surface, said borderdefininga set back adjacent the connection between the projectile and the plate,whereby threads are prevented from being caught between the'projectileand the plate.

' 8. A gripper point according to claim 1 wherein the spring blade isconnected to the plate by means of adjustable tightening means.

1. A gripper point for loom projectiles with an external feed,comprising a plate, a rocker strip and a spring blade, said rocker strippivoting about an axis parallel to said plate and supported by saidplate, said spring blade bearing resiliently on said rocker strip nearone end thereof in order to press said rocker strip against said plate,said plate and said rocker strip having in the area in which they arepressed against one another surfaces for gripping a weft thread, andsaid plate being provided with a hook for guiding a wefT thread towardthe gripping surfaces.
 2. A gripper point according to claim 1 whereinthe plate and the rocker strip are positioned with respect to oneanother by a rib and a groove, one being on the plate, and the other onthe rocker strip, the groove and rib determining the pivoting axis.
 3. Agripper point according to claim 1 wherein the surfaces that grip a weftthread have complementary deformations.
 4. A gripper point according toclaim 3 wherein the complementary deformations on the gripping surfacesextend beyond the gripping surfaces toward the hook for guiding the weftthread.
 5. A gripper point according to claim 1 wherein the rocker striphas a tail extending beyond the pivoting support, while the spring bladehas an opening for the passage of the tail, the arrangement of the tailbeing such that its end extends through the opening.
 6. A gripper pointaccording to claim 1 wherein the rocker strip has at its end a tip, thecontour of said tip continuing the profile of the outer surface of thespring blade.
 7. A gripper point according to claim 1 wherein the platehas a border at its end on the face opposite the gripping surface, saidborder defining a set back adjacent the connection between theprojectile and the plate, whereby threads are prevented from beingcaught between the projectile and the plate.
 8. A gripper pointaccording to claim 1 wherein the spring blade is connected to the plateby means of adjustable tightening means.